In the field of food processing, it is well known that excess fat is removed from the back of the loin of an animal before cutting and or packing the meat for marketing. Typically, the carcass of an animal is cut into two halves, the left and right sides of the animal. Each carcass half includes a loin to be removed from the back fat. The loin is adjacent to the back bone and is situated between the ribs and the outer layer of fat, which is to be removed.
Typically, the loins are removed from the carcass halves by using hand-manipulated knives pulled from one end of the carcass to the other. The knives are contoured to match the curvature of the loins. Such manipulation has been known to cause physical problems from the repetition of this process many times an hour.
Several automatic devices have been developed to provide the same or similar functions of the hand-manipulated knives in a more time-efficient and less physically detrimental manner. Typical of the art is the device disclosed in U.S. Pat. No. 4,189,806 issued to W.P. Van Heyningen on Feb. 26, 1980 and Canadian Pat. No. 1,079,114 issued on Jun. 10, 1980. Each of these patents discloses the same invention. Reference will be made to the U.S. Pat. No., and may be referred to as "the '806 patent".
The devices that have been developed and which are known have not yet enabled the loin to be removed from the back fat without requiring the further splitting of the carcass halves into quarters. The device disclosed in the '806 patent requires that the loin portions be first separated from the carcass halves or sides by cutting straight through the scribed ribs and tissues. It is desirable, however, to remove the loin from the carcass halves without necessitating the quartering of the carcass.
The cutting blade used in the '806 device has a fixed symmetrical shape such that both loins may be removed with the same device. However, the desired cut does not define a constant geometric configuration over the length of the loin. The desired width of the cut is greater at one end of the loin than at the other.
Several other devices have been developed to separate loins from excess back fat, typical of which are described in U.S. Pat. Nos. 3,546,737 issued to R. Neeble, et al., on Dec. 15, 1970; U.S. Pat. No. 3,771,196 issued to R.F. Doerfer, et al., on Nov. 13, 1973; and 4,979,269 issued to L.W. Norrie on Dec. 25, 1990.
It is well known in the field of butchering that when separating the fat from the loin, a more efficient cut is made when the cutting blade is heated. Hand-manipulated blades are typically dipped in hot water to aid in heating the blade. The device disclosed in U.S. Pat. No. 3,352,011 issued to C.J. Alexander, et al., on Nov. 14, 1967 is an electrically-heated, hand-manipulated blade. However, it is not intended for this device to be used in conjunction with automatic machinery such as that of the present invention. Automatic devices have not yet been provided with a means for heating the cutting blade.
Therefore, it is an object of this invention to provide a means for trimming the back fat from loin in the food processing industry.
Another object of the present invention is to provide a means whereby the loin may be removed from a carcass half without requiring the quartering of the carcass.
It is also an object of the present invention to provide a means whereby the width of the cut may be selectively varied over the length of the cut along the carcass.
Still another object of the present invention is to provide a means whereby the cutting blade may be heated to ease the removal of excess back fat from the loin.
Yet another object of the present invention is to provide a means for retaining the rib portion of the carcass half and further for simultaneously conveying the rib portion along with the loin portion which has been cut from the back fat.
Still another object of the present invention is to provide a means whereby excess fat may be cut from the rib portion of the carcass half being pulled.